Applying mixture cure survival modeling to medication persistence analysis.

PURPOSE: Standard survival models are often used in a medication persistence analysis. These methods implicitly assume that all patients will experience the event (medication discontinuation), which may bias the estimation of persistence if long-term medication persistent patients rate is expected in the population. We aimed to introduce a mixture cure model in the medication persistence analysis to describe the characteristics of long-term and short-term persistent patients, and demonstrate its application using a real-world data analysis. METHODS: A cohort of new users of statins was used to demonstrate the differences between the standard survival model and the mixture cure model in the medication persistence analysis. The mixture cure model estimated effects of variables, reported as odds ratios (OR) associated with likelihood of being long-term persistent and effects of variables, reported as hazard ratios (HR) associated with time to medication discontinuation among short-term persistent patients. RESULTS: Long-term persistent rate was estimated as 17% for statin users aged between 45 and 55 versus 10% for age less than 45 versus 4% for age greater than 55 via the mixture cure model. The HR of covariates estimated by the standard survival model (HR = 1.41, 95% CI = [1.35, 1.48]) were higher than those estimated by the mixture cure model (HR = 1.32, 95% CI = [1.25, 1.39]) when comparing patients with age greater than 55 to those between 45 and 55. CONCLUSIONS: Compared with standard survival modeling, a mixture cure model can improve the estimation of medication persistence when long-term persistent patients are expected in the population.

Employer-based health initiative: impact on employees' cardiovascular outcomes.

BACKGROUND: Cardiovascular disease is the primary cause of mortality among men and women in the United States. The Ready, Set, Goal program was an employer-based initiative designed to identify individuals at risk for cardiovascular disease and to offer an intervention to alter those risk factors. The program involved cardiovascular education, screening, behavior-change incentives, continuing assessment, and follow-up. Pharmacologic treatment was not part of the intervention. OBJECTIVE: To analyze the effects of the Ready, Set, Goal pilot program in 5 employers in the United States on salient cardiovascular end points for employees who completed the program. METHODS: The analysis used a pretest/posttest within-subjects design to compare baseline measurements with measurements for all subjects who completed a second assessment 6 months after baseline measurements. Enrollment began in June 2004 in the first site and in May 2005 in the last site; it ended in January 2006. Patient clinical data from the pilot interventions were aggregated to assess the effects of the intervention on salient cardiovascular end points for individuals who completed the Ready, Set, Goal program. Changes in short-term cardiovascular risk factors were evaluated. Descriptive measures with paired t-tests (α = 0.05) were calculated at the aggregate level for each dependent variable. Range checks were conducted on all variables for clinical validity. RESULTS: A total of 589 subjects from 5 employer group pilot interventions completed the program. Of these, 43% were men, 60% were white, 9% were African-American, 11% were Hispanic, and 20% were categorized as "other." After the intervention, mean blood pressure, total cholesterol, and low-density lipoprotein cholesterol levels were significantly lower (P <.05) compared with baseline measurements. On average, systolic blood pressure declined by 1.9 mm Hg; diastolic blood pressure by 1.3 mm Hg; total cholesterol decreased by 5.2 mg/dL and low-density lipoprotein cholesterol by 3.4 mg/dL. Triglyceride levels increased and high-density lipoprotein levels decreased, although these changes were not significant, and neither were the mean increases in body weight. But increases in body mass index were significant. CONCLUSIONS: A worksite cardiovascular health program can have positive effects on salient cardiovascular end points for employees. The increases in triglyceridnes and body mass index should be further explored.

Managed care and the impact of glaucoma.

Changes in the healthcare system, population demographics, and treatment alternatives have contributed to an emerging awareness of glaucoma among managed care organizations. Early diagnosis and treatment are essential to thwarting the personal and economic consequences of end-stage glaucoma. Despite recognition of the need for early intervention and therapy, the literature suggests a great need still exists for improvements in lowering intraocular pressure, managing appropriate follow-up, and improving adherence to current glaucoma medication regimens. As the elderly population continues to increase, these issues will intensify and present further problems for the healthcare system. The purpose of this introductory manuscript is to highlight the literature on the clinical and economic impact of glaucoma and its importance to the managed care community. The remainder of the supplement will focus on the current management of glaucoma and the potential role of neuroprotection in this patient population.

Current landscape of insomnia in managed care.

Insomnia affects a large percentage of the population, particularly the elderly. Literature reports varying estimates of prevalence, a variation that relates to the lack of definition and consistency in diagnostic criteria. Primary insomnia (not caused by known physical/mental conditions) responds to pharmacologic therapy, while secondary insomnia(resulting from other illnesses, medications, or sleep disorders) responds to pharmacologic and psychologic treatments (cognitive therapy, relaxation techniques, stimulus control). Use of certain agents in the elderly and patients with abuse/addiction potential is a concern. Medicare Part D does not cover benzodiazepines (classified as controlled substances). Nonprescription agents are affordable but have sedation and anticholinergic side effects. Medication use should be considered a possible contributing factor. Insomnia patients experience significantly more limited activity and higher total health services than those without insomnia. Annual costs are between $92.5 billion and $107.5 billion. A standard definition and better pathways to recognize and treat insomnia are needed.

Managing oncology costs.

This monograph will review the burden of illness in oncology, suggest a framework for evaluating oncology costs and consequences, identify economic modeling formats in cancer care, and explore methods of cost control for cancer care.